“Nobody can come up with a solution. He’s never hungry and never asks for food. He totally relies on his tube feeding, it’s where he gets all his nutrients.” Tests by dieticians as well as speech and occupational therapists have all drawn a blank. Genetics experts are also investigating.

They first noticed issues with Steven when they tried to wean him off milk as a tot. Accounts assistant Nicola said: “Whether he can’t or won’t chew, we’re not sure. They think he might have a sensory problem within his mouth, but that’s not been confirmed.”

She said Steven is unfazed by his problem as he knows no different. But she asked parents with similar experiences to get in touch. She said: “It would be helpful to swap ideas.”